This patch adds the ability to detect and manage GPU and Disk expansion
bays, and either add their internal components into the device
corresponding to the blade server, or into a dedicated device.
It takes advantage of the work made by @cyrinux on GPU bays management, and
applies the same principle to the external disk bays, but harmonize the
inventory management:
- If no argument is specified on the command line, the GPU cards, RAID
controllers and their attached disks are added in the blade device,
and the device corresponding to an expansion device is deleted.
- If the `--expansion-as-device` option is specified on the command
line, a dedicated device corresponding to the expansion bay is
created, and the GPUs, RAID card and attached disks are removed from
the blade device and added to the expansion device.
